A temperature color mapping of the effects of a closed Bering Strait. The northern Pacific cools while the northern Atlantic warms significantly enough to bully Norther American climate. (Source: Nature/UCAS)

The unassuming 53 mile Bering Strait hardly seems like the type of geological formation that would cause this kind of trouble. (Source: Wikipedia commons)

It comes down to one little strait and some really big sheets of ice.

The
Bering Strait, spanning a distance of approximately 53 miles between
Alaska and Russia, looks like an unassuming place for temperature
regulation for the entire North American region (including
Greenland), but recently published NCAR/UCAR findings seem to
indicate that it may be very geologically important.

The
strait serves as a gate for cooler, less salinized water from the
Pacific to flow to the warmer and saltier Atlantic. Their simulations
found that without this flow, the climate of North America fluctuates
much more rapidly – in the span of a few thousand years rather than
some tens of thousands – and helps explain constant temperature and
ice sheet modulation between 116,000 and 34,000 years ago, a time of
constant ice sheet advance and retreat.

In the past, this
pattern was often attributed to the Earth’s position along its
95,000 year orbital pattern, but the NCAR researchers found that when
correlated with the temperature and ice data, the orbit could not
explain the rapid fluctuations. Instead, it occurred to them that
changes to the Bering Strait itself could have a large impact on the
entire region due to the changes it would bring to the Pacific and
Atlantic ocean currents. Their models indicate that a slight change
in the strait would adversely affect the meridional overturning
circulation, an ocean current which helps drive the Atlantic
tropics-to-polar heat pump.

In
the simulation, they show that around 110 to 115 thousand years
ago, the northern climate cooled sufficiently to create giant ice
sheets over the northern regions of North America and all of
Greenland. As these ice sheets sucked up water from the global
oceans, sea levels dropped by as much as 100 feet. Eventually a vast
amount of the strait was no longer able to pass water – the average
depth of the strait is 100 - 190 feet. The new land bridge cut off a
vast portion of the ocean flow between the Pacific and Atlantic.
This, in turn, caused the Pacific ocean to become even cooler and
cleaner, but allowed the now saltier waters of the Atlantic to push
the meridional overturning circulation into overdrive, warming the
regional ocean, North America and Greenland by as much as 1.5C over a
few thousand years.

Next, the regional warming caused the iced
sheets to melt over another few thousand years, returning the oceans
to their previous depth and reopening the Bering Strait. With the
Atlantic’s access to cooler and cleaner water from the Pacific
restored, the cycle started all over again.

These temperature
oscillations went on like a driver overcompensating for an icy road
fishtail until finally, around 34,000 years ago, the Earth’s
distance from the sun was so great that it literally froze the
fluctuation in place. About 10,000 years ago, the Earth had finally
gotten close enough to the sun again to warm up the northern
hemisphere to the point where the strait reopened slowly and the
temperature variations settled into a much more docile animal.

This
study helps to provide convincing data for two things: that a
significant change in something even so geographically small can
adversely affect the climate of an entire quadrant of hemisphere, if
not an even greater area, and that the planet has its own regulatory
devices to deal with such things. However, it remains to be seen how
long the cycle would have gone on if not for the fortuitous position
in the orbital cycle. Too, this study reflects nothing at all of
man’s influence on these climate systems in current times. The key
to understanding these things lies in first understanding the basic
driving forces behind climate systems and the NCAR study has shown us
how one such small system may operate.

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quote: But that all supports the current theories of climate change. The buffers are getting full. Oceans are becoming more acidic as they absorb CO2 in the form of carbonic acid. Atmospheric CO2 as a percentage is way up in the last 150 years.

I agree that CO2 is a problem, but only a recent problem, and not the only problem. Methane is also an issue which has been influencing things long before CO2 joined in. And yes, the ocean buffers are getting full. (For those of you wondering what were babbling about, you can get an idea by looking at PH versus Alkalinity. Any salt water aquarist should be familiar with that.)

I know it's a touchy subject but we really do need to invest heavily in nuclear power. For all its problems, its solves so many more problems. And I too would be happy to not send our wealth overseas, especially to those that hate us.

Why? It's airborne plant food. It's also very good at preventing ice ages...a climate change event that we're overdue for, and one that could kill billions of people.

The only risk of CO2 is the silly belief that it can cause some positive-feedback cycle that would result in runaway warming, despite tons of evidence to the contrary. But then people WANT to believe CO2 is bad, to justify some misguided anti-consumption, anti-capitalist agenda.

I think your failing to see the main danger with our effecting the atmosphere.

In nature, change happens. Some don't survive it, most do. The trees that currently exist in the cold of northern Canada used to be here in Virginia. But as the earth warmed, they naturally migrated north to their present location. Change can even be good. The failure of one species to adapt to change provides an opportunity for other species.

In nature, rapid change is always bad. To much change to fast wipes out a huge number of species. Whole ecosystems collapse. Eventually things come back but it takes time.

The concern to me is will we cause change that is to fast for nature to adjust to without huge pain. Or we will we cause the temperatures to go higher than they normally would, or even colder.

To make this more "human", imagine this. Temperatures warm and suddenly areas that grew lots of food can't, and areas they couldn't now can. Do you not think that's going to be a source of conflict between the former 'haves' and the 'haves not'? What if Kashmir suddenly become incredibly productive? Do you think India and Pakistan wouldn't go at each other over it in order to feed their starving populations? And both have Nuclear weapons.

Again, change is. But if it changes to fast it can cause a lot of pain adjusting to it.

"Intel is investing heavily (think gazillions of dollars and bazillions of engineering man hours) in resources to create an Intel host controllers spec in order to speed time to market of the USB 3.0 technology." -- Intel blogger Nick Knupffer